Roofing system with sensors

ABSTRACT

A rooting method and system in which sensors are placed on the roof substrate, and a water impermeable membrane is placed over the sensors. This can be accomplished by applying the sensors and membrane separately, or by applying a membrane which incorporates the sensors. The sensors may be selected so as to provide strain and temperature information. A system monitoring this information may provide an alert if a roof leak or excessive strain is detected.

CLAIM OF PRIORITY TO PRIOR APPLICATION

This application claims priority to provisional patent application Ser. No. 61/952,532, filed Mar. 13, 2014, and entitled Roofing System with Sensors.

FIELD OF THE INVENTION

The present invention relates to roofing systems.

BACKGROUND OF THE INVENTION

Rain, heavy snow and roof gardens can place a great strain on many roofing structures. Over time, even a small leak can lead to catastrophic failure if not discovered and fixed. A roofing failure cannot only lead to damage and loss of property, it can also be very dangerous.

SUMMARY OF THE INVENTION

The present invention comprises a roofing method and system in which sensors are placed on the roof substrate, and a water impermeable membrane is placed over the sensors. This can be accomplished by applying the sensors and membrane separately, or by applying a membrane which incorporates the sensors. The sensors may be selected so as to provide strain and temperature information. A system monitoring this information may provide an alert if a roof leak or excessive strain is detected.

These and other objects, advantages, purposes and features of the present invention will become more apparent upon review of the following specification in conjunction with the drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG, 1 is a perspective view of a building showing roofing membrane in accordance with a preferred embodiment of the present invention;

FIG. 2 is a perspective view of a building for which sensors have been placed on the roof substrate, and membrane is being applied over the sensors;

FIG. 3 is a plan view of a scrim incorporating sensors;

FIG. 4 is a sectional view of the roofing membrane of FIG. 1;

FIG. 5 is an exploded view of the roofing membrane of FIGS. 1 and 4;

FIG. 6 is a sectional view of an alternative embodiment sensor membrane;

FIG, 7 is a sectional view of a second alternative embodiment sensor membrane.;

FIG. 8 is a sectional view of a third alternative embodiment sensor membrane;

FIG. 9 is a sectional view of a fourth alternative embodiment sensor membrane: and

FIG. 10 is a schematic of a roof monitoring and reporting system of the preferred embodiment.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

In the preferred embodiments, the roofing system of the present invention may comprise a roofing membrane 20 incorporating sensors as shown in FIGS. 1, 3, 4 and 6-9, or may comprise sensors applied directly to the roof substrate, and then covered with a membrane 20A as shown in FIG. 2. In either of those alternatives, the sensors can be incorporated into a scrim layer 40 as shown in FIG. 5, which is then either laid on the roof substrate 12 and covered with a separate water impervious membrane 20A, or which is adhered directly onto a water impervious membrane layer 30, as shown in FIG. 4. Alternatively, sensors 50 may be incorporated directly into the water impervious membrane layer 30 as shown in FIGS. 6-9. Preferably sensors 50 are elongated sensor strands, most preferably fiber-optic strands. Fiber-optic strands can identity water leaks by identifying temperature changes which affect the optical signal, and can identify roof strain due to deflection of the fibers, which affect the optical signal.

Referring now to the drawings and the illustrative embodiments depicted therein, a roofing membrane or sheet 20 used for covering a rooftop 12 on a building 10 comprises a sensor or sensing layer 40 and a water impervious cover or coating layer or membrane 30. Sensing layer 40 includes a plurality of fiber-optic sensors 50 adhered, sewn or woven into a geotextile fabric or other scrim 46. Sensors 50 are configured to measure changes in temperature and/or strain. Membrane layer 30 covers a top surface 42 of sensing layer 40. One or more sheets 20 can be installed on rooftop substrate 12 and seamlessly fused together with an additional layer of coating, providing a water tight seal over rooftop 12. A monitoring system 60 monitors the output of sensors 50 and issues an alert to a receiving device 70 in the event of a leak in sheet 20 or excessive strain on rooftop 12 or the like.

Each roofing membrane layer can come in varying sizes. Widths typically vary from 5 to 15 feet, and can be conveniently supplied in rolls as long as 300 feet. When membrane units 20 are butted endwise, the sensors 50 are connected using conventional coupling methods. The spacing within a membrane layer 20 can vary, but a spacing of one sensor 50 every 2 to 4 feet is exemplary.

In the FIG. 2 embodiment, sensors 50 are laid onto roof substrate 12, either as individual strands, or incorporated into sensor scrim 40 as described above. Roofing membrane 20A which does not incorporate sensors is then applied over the layer of sensors 50. At their ends, sensors 50 are connected to a communication strand 51 and 52, which connect them to monitor 62 via communication links 66 (FIG. 10).

Referring now to FIG. 3, sensing layer 40 is a sensor enabled geotextile, available from sources such as TenCate, a division of Royal Ten Gate of the Netherlands, under the brand name GEODETECT. Sensing layer 40 comprises a scrim or fabric 46 made from a composite geotextile material and a plurality of fiber-optic sensors 50. Preferably, scrim 46 is porous, especially when the fiber-optic sensors are located between scrim 46 and water impervious layer 30 (FIG. 4). This allows water leakage to gain access to fiber-optic sensors 50. Alternatively, scrim 46 can be sufficiently thin that temperature variations caused by water leakage can be sensed at the fiber-optic sensors 50. In the illustrated embodiment, sensing layer 40 is essentially rectangular in shape with four edges 48 a, 48 b, 48 c, and 48 d. Sensing layer 40 has a top surface 42 and a bottom surface 44. Sensors 50 run lengthwise across top surface 42 and are adhered, sewn to or interwoven into fabric 46.

As illustrated in FIGS. 4 and 5 membrane 30 is applied to sensing layer 40 covering at least top surface 42. Membrane 30 is formed from a spray coating that when applied to sensing layer 40 creates a waterproof layer having a top surface 32 and a bottom surface 34. In the illustrated embodiment, membrane 30 is generally rectangular in shape with four edges 36 a, 36 b, 36 c, and 36 d corresponding to edges 48 a-48 d of sensing layer 40, respectively. While membrane 30 may be any number of water resistant coatings and thicknesses, the illustrated embodiment uses an 80 mil spray coating of polyurea. Polyurea spray coatings can provide fast curing, even at very low temperatures, and water resistance, along with high hardness, flexibility, and tear strength. Although sensor layer 40 and membrane layer 30 are shown in the illustrated embodiment as generally rectangular, it should be appreciated that alternative shapes, styles and configurations may be utilized.

Other coating methods may be employed for applying water impervious layer 30, e.g. via roller, squeegee, knife blade, extrusion or pultrusion. Other examples of membrane materials include without limitation EPDM, TPO, PVC and Hypalon.

FIG. 6 shows an alternative embodiment roofing membrane 20 in which the water impervious layer is applied to the reverse side of scrim 46, from that shown in FIGS. 4 and 5, such that sensors 50 are exposed to the roof substrate when roofing membrane 20 is applied. In the FIG. 6 embodiment, sensors 50 are incorporated directly into the water impervious layer 30. When encapsulated in this manner, sensors 50 are preferably sufficiently close to the bottom surface of layer 30 that they sense temperature changes due to the presence of water. In the FIG. 7 embodiment, sensors 50 are embedded into the bottom of water impervious membrane layer 30, such that they are partially exposed. In the FIG. 9 embodiment, sensors 50 are simply adhered to the undersurface of water impervious layer 30.

One or more roofing sheets 20 are installed on rooftop 12 and seamlessly fused together with additional sprayed polyurea or other polymer layer or layers that are disposed over the top of the membrane layer 30. Once installed, sheets 20 become part of a rooftop monitoring system 60 (FIG. 5). Monitoring system 60 comprises one or more sheets 20, an optical interrogator 62, a computing unit 64, and a communications link 68 between optical integration 62 and computing unit 64. Sensors 50 in sheet 20 can measure conditions and/or changes in conditions, such as by measuring the strain and/or temperature on rooftop 12. Sensors 50 incorporate one or more fiber-optic sensing technologies such as Fiber Bragg Gratings, Brillouin, and Raman technologies. These technologies are able to measure temperature and/or strain very precisely and with a relatively high spatial resolution under static or dynamic conditions. Optical interrogator 62 collects strain and temperature data from sensing layer 40 via a wired or fiber-optic connection 66. Monitoring may be continuous or periodic. Interrogator 62 may include a number of channels for receiving data from sensing layer 40 and each channel may sample at different rates. Data received by interrogator 62 is then transmitted to computing unit 64 via communications link 68. Computing unit 64 may be located on-site or located remotely, and communications link 68 may be a wired connection or a wireless connection. Once data is received by computing unit 64 the data is analyzed. When computing unit 64 senses a warning condition, such as a change in temperature suggestive of a leak or high strain indicating heavy snow accumulation on rooftop 12, computing unit 64 issues an alert to a receiving device 70. Receiving device 70 may be a personal computer, smartphone, cell phone, or the like. The alert may be in the form of an email, phone call, text message or the like.

Optionally, interrogator 62 may be capable of analyzing, the data for warning conditions. In this case, interrogator 62 can issue the alert directly to receiving device 70 without the need the computing unit 64.

Changes and modifications to the specifically described embodiments may be carried out without departing from the principles of the present invention, which is intended to be limited only by the scope of the appended claims as interpreted according to the principles of patent law including the doctrine of equivalents. 

1. A roof covering system comprising: a waterproof membrane having integrally joined therewith a plurality of sensors for sensing roof conditions.
 2. The roof covering system of claim 1 comprising: said plurality of sensors being secured to a scrim; said waterproof membrane being affixed to and overlying said scrim.
 3. The roof covering system of claim 2 wherein said sensors comprise fiber-optic sensors.
 4. The roof covering system of claim 3 in which said scrim includes a top and a bottom surface, said fiber-optic sensors being located on said top surface of said scrim, and said waterproof membrane being secured to said top of said scrim, with said fiber-optic sensors located between said scrim and said waterproof membrane layer.
 5. The roof covering system of claim 4 in which said scrim is porous, such that water seeping beneath said scrim will make contact with said fiber-optic sensors.
 6. The roof covering system of claim 3 in which said scrim includes a top and a bottom surface, said fiber-optic sensors being, located on said bottom surface of said scrim, and said waterproof membrane being secured to said top of said scrim.
 7. The roof covering system of claim 3 in which said waterproof membrane layer is affixed to said scrim by coating said scrim.
 8. The roof covering system of claim 7 in which said membrane is made of polyurea.
 9. The roof covering system of claim 1 comprising: said sensors being joined directly with said waterproof membrane.
 10. The roof system of claim 9 in which said sensors are fiber-optic sensors.
 11. The roof covering system of claim 9 comprising: said sensors being encapsulated in said waterproof membrane.
 12. The roof system of claim 11 in which said sensors are fiber-optic sensors.
 13. The roof covering system of claim 9 comprising: said sensors being adhered to the undersurface of said waterproof membrane.
 14. The roof system of claim 13 in which said sensors are fiber-optic sensors.
 15. The roof covering system of claim 9 comprising: said sensors being embedded in said waterproof membrane.
 16. The roof system of claim 15 in which said sensors are fiber-optic sensors.
 17. The roof covering system of claim 9, further comprising said sensors being operably connected to a computer for interpreting the information provided by said sensors.
 18. The roof covering system of claims 17 in which said operable connection of said sensors to said computer comprises a transmitter for wirelessly communicating information provided by said sensor to said computer.
 19. The roof covering system of claim 3, further comprising said sensors being operably connected to a computer for interpreting the information provided by said sensors.
 20. The roof covering system of claims 19 in which said operable connection of said sensors to said computer comprises a transmitter for wirelessly communicating information provided by said sensor to said computer.
 21. The roof covering system of claim 1, further comprising said sensors being operably connected to a computer for interpreting the information provided by said sensors.
 22. The roof covering system of claims 21 in which said operable connection of said sensors to said computer comprises a transmitter for wirelessly communicating information provided by said sensor to said computer.
 23. A roofing system comprising: a plurality of sensors placed on a roof substrate, and a water impermeable membrane placed over said sensors.
 24. A method of monitoring roof conditions comprising: placing a plurality of sensors on roof substrate, and placing a water impermeable membrane placed over said sensors.
 25. The method of claim 24 in which said placing steps are accomplished in a single step by placing on said roof substrate a waterproof membrane having integrally Joined therewith a plurality of sensors for sensing roof conditions. 